High Risk Groups
Those at high risk of being infected with HCV are:
- People who received blood transfusions or blood products before the introduction of routine blood screening in the early to mid-1990s.1 They may have included people with haemophilia, solid-organ transplants, chronic renal failure, cancer requiring chemotherapy or those who were in an accident and required a blood transfusion. Some mothers who received the blood product anti-rhesus factor after giving birth were also infected.
- People in developing countries where unscreened blood products and un-sterilised injection equipment remain the major route of transmission.2
- Injecting drug users (IDUs) including those who experimented with injecting drugs years ago. Evidence suggests that 37 to 98 per cent of past and present injecting drug users may be infected with HCV.3 Also, other parenteral routes administration, like snorting cocaine and smoking crack cocaine, have been associated with a high risk of acquiring HCV.
- People who practise unprotected high-risk sexual behaviour, have unprotected sex with multiple partners or have already acquired a sexually transmitted disease. The US Centers for Disease Control and Prevention estimate that about 15 per cent of hepatitis C cases resulted from sexual exposure.4 Although the risk of HCV infection through sexual intercourse is low, sex is a common behaviour and, with a large number of people having unprotected sex with a number of different partners, the risk of exposure to the hepatitis C virus can be high in some parts of the population. This is especially so given the large size of the hepatitis C population.5
- Children born to mothers infected with HCV. Between 3 and 15 per cent of pregnant women in the US and Europe test positive for HCV, and five per cent will pass the virus to their children by the time they are born.5 Pregnant women with hepatitis C who have either a high viral load or are co-infected with human immunodeficiency virus (HIV) are more likely to transmit the virus to their offspring. However, the virus does not appear to be transmitted through breast-feeding.
- Healthcare workers who suffer needle stick injuries. The risk of transmission after a puncture wound with HCV-contaminated material is about 1 to 4 per cent.
- People whose tattooing, piercing or other body modifications were carried out with inadequately sterilised equipment.
- Those who have had surgical, dental or acupuncture treatment where equipment may have been inadequately sterilised or where syringes were reused.6
Those at slightly increased risk include:
- People who use non-injected recreational drugs such as cocaine. In this case, transmission of HCV could take place through sharing blood-contaminated straws or bank notes to snort drugs.
- Sharing of contaminated items like razor blades, nail clippers, barber scissors and even toothbrushes, although these methods of transmission are rare.
With the exception of sexual partners, the use of good hygiene (not sharing toothbrushes, razors, etc) makes the risk of transmission between family members negligible.
1. National Institutes of Health Consensus Development Conference Statement: Management of hepatitis C; June 10-12, 2002. Hepatology 2002;36 (5 Suppl 1):S3-20.
2. Shepard CW, Finelli L, Alter MJ. Global epidemiology of hepatitis C virus infection. Lancet Infect Dis 2005;5(9):558-67.
3.Mathei C, Buntinx F, van Damme P. Seroprevalence of hepatitis C markers among intravenous drug users in western European countries: a systematic review. J Viral Hepat 2002;9(3):157-73.
4. National Center for Infectious Diseases. National Hepatitis C Prevention Strategy. 2006.
5. Initiative for Vaccine Research, Viral Cancers, Hepatitis C. World Health Organization, 2006. (Accessed January, 2007, at http://www.who.int/.)
6. Miller MA, Pisani E. The cost of unsafe injections. Bull World Health Organ 1999;77(10):808-11.